X-ray tube



Patented M0913, l1921 Y T. s, RIDER.

cathode when completing its fall in ment at 22 and .a different point in the cathode and anode of such an ment on the part of the cathode forward or backward. The operator is then certain that the cathode is at the same focal spot in relation to the anode as before.

The action disengages the recesses 30 in the disk face in the end 27 of the sleeve member 24 from the projecting members 28 ondthe cathode body 29. In this condition an to turn on the stem 15 except for the friction member 37 actuated by the spring 32 in the cathode member which prevents an undesired turning of the cathode member on the stem.

The X-ray tube is then turned t0 stand on enclin the opposite direction. The spring or friction member 20a is designed so as to retard the falling of the weighted member while the sleeve member with the disk end 27 is so loosely mounted on the stem 15 that the recesses 30 engage with the projecting members 28 on the cathode 29 before the weighted member in its movement toward the cathode.

While the sleeve member is so already engaged with the cathode, the weighted member still continuesr its movement toward the cathode. The Weighted member 21, being prevented from turning on the stem by the key and keyway engage- 23, causesa turning of the sleeve member 24 andthereby a turning of the cathode on the stem since the sleeve is compelled to slide over the body 3ft of the weighted member 21 in a spiral direction along the spiral ridges 36 and grooves 35.

Through this operation, the cathode is turned andmoved to a position to focus to face of the anode 7. manner changed at without any outside The focus is in this the will of the operator mechanism to help or for controlling the focus between the X-ray tube. A11 the operator has to do is to tilt the X-ray' tube in the described lmanner for disengag- .ing and engaging the diderent recesses and vprojecting members between the sleeve member 'and the cathode to cause the weighted member to accomplish the turning of the the direction toward the cathode, as described above. v

i In' Fig. II,.the cathode illustrated'in engaged and operative position, set and adusted to focus to a certain point inthe face ofthe anode.

at such a moment the cathode is free 21 reaches its termination y influence the device Having thusvdescribed my invention, I claim:

1. In an X-ray tube in combination with the cathode in such tube having Vits face disposed eccentrically on its supporting body on a centrally disposed Stem in the tube, operating means disposed on the stem for a sliding movement, and means operatively engaged with the operating means for turning the cathode on the stem by such sliding movement.

2. In an X-ray tube in combination with the cathode in such tube having its face eccentrically disposed on its supporting body, a centrally disposed stem in the tube, a weighted member slidingly disposed on the stem, and another member turnably and slidably disposed on the stem having means engaging with the weighted member for a longitudinal and turning movement in re a turning member disposed on tlie Stem ha`v-l ing means for when moved toward the cathode, a Weighted member slidingly disposed on the stem having spiral engaging means, and other spiral enea ine means on the turnin member cor.

h h g responding to the spiral engaging means on the Weighted member for producing a turning movement to the turning member when the weighted member is caused to slide on the stem.

y 4. In an X-ray tube, a centrally disposed cathode stem, a cathode turnably disposed on the end of. the stem having its focusing face eccentrically disposed transversely to the stem, friction means disposed between the cathode and the stem, engaging means in the rear end of the cathode, turning means on the stem having means for engaging with the engaging means on the rear end of the cathode, sliding means disposed on the stem, friction lmeans disposed between the stem and the sliding means, and spiral engaging means disposed between the sliding means and the turning means.

In testimony whereof I Vhereunto atlix my signature in the presenceof two witnesses. Y

THOMAS B. RIDER.

VVitneslses 'it C. M. ENNs,

J. H. RYCKMAN.

engaging with the cathode` 

